How to Calculate the Landed Cost of Imported Natural Stone
August 9, 2026 · 25 MIN READ
When importing natural stone internationally, the supplier’s quoted price is rarely the true cost of the purchase.
A block priced at $20,000 at the quarry can ultimately cost substantially more by the time it reaches the buyer’s warehouse, stone yard, fabrication facility, or project site.
Between the supplier and the final destination, an importer may incur costs related to inland transportation, export handling, ocean freight, insurance, customs clearance, duties, taxes, port charges, terminal handling, documentation, storage, inspection, and final delivery.
This is why professional natural stone buyers should evaluate landed cost, not simply the supplier’s quoted stone price.
The landed cost provides a more realistic picture of what the imported stone actually costs the buyer after the relevant costs required to bring it to the agreed destination are accounted for.
This distinction is especially important when comparing suppliers offering different Incoterms such as EXW, FOB, CFR, or CIF.
What Is Landed Cost?
Landed cost is the total cost incurred to acquire imported goods and bring them to the buyer’s defined destination or point of use.
For natural stone, a simplified framework is:
Landed Cost = Product Cost + Origin Costs + International Transportation + Insurance + Import Costs + Destination Costs + Other Applicable Costs
However, there is no single universal formula that applies identically to every country or shipment.
The exact components depend on:
- The Incoterm
- Country of export
- Country of import
- Transport mode
- Customs classification
- Customs valuation rules
- Applicable duties
- Import taxes
- Port and terminal charges
- Insurance arrangements
- Delivery destination
- Shipment type
- Contract structure
Therefore, a professional landed-cost calculation should begin by identifying what is already included in the supplier’s quotation.
Landed Cost vs. Customs Value
One of the most important distinctions for importers is that landed cost and customs value are not the same thing.
Customs value is a valuation concept used by customs authorities, particularly for determining ad valorem customs duties and other customs-related purposes.
Under the WTO Customs Valuation Agreement, the primary method is generally the transaction value—the price actually paid or payable for the imported goods when sold for export to the country of importation, subject to specified adjustments and conditions.
The World Customs Organization also emphasizes that the customs value does not necessarily equal the invoice value in every case. Certain adjustments may be required, depending on the applicable customs valuation rules.
Landed cost, by contrast, is a commercial calculation used by the importer to determine the actual economic cost of obtaining the goods at the defined destination.
For example:
Customs Value ≠ Landed Cost
A shipment can have a customs value of $25,000 while its total landed cost is significantly higher after freight, duties, insurance, handling, clearance, and destination transportation are considered.
This distinction should be maintained throughout the calculation.
Why Landed Cost Matters for Natural Stone
Natural stone is particularly sensitive to landed-cost analysis because it is:
- Heavy
- Relatively expensive per shipment
- Often shipped internationally
- Sensitive to transportation costs
- Subject to handling and packaging requirements
- Commonly traded under different Incoterms
- Sold in blocks, slabs, tiles, or fabricated products with very different logistics profiles
A supplier with a lower stone price may therefore produce a higher landed cost if its logistics structure is less efficient.
Consider two hypothetical offers:
Supplier A:
Stone price: $22,000
Supplier B:
Stone price: $25,000
At first glance, Supplier A appears $3,000 cheaper.
But suppose Supplier A requires the buyer to pay significantly more for inland transportation, freight, insurance, handling, and destination costs.
Supplier B may ultimately be the less expensive option.
This is why professional procurement decisions should be based on comparable landed cost, not headline product price.
The Basic Landed Cost Formula
A useful starting framework is:
Landed Cost = Purchase Price + Origin Costs + Main Freight + Insurance + Import Costs + Destination Costs
Where applicable, this may include:
Purchase Price
The agreed price of the natural stone.
Origin Costs
Costs incurred before the international main carriage, depending on the Incoterm.
Examples may include:
- Factory handling
- Loading
- Inland transportation
- Export documentation
- Export customs clearance
- Port handling
Main Freight
The international transportation cost.
For maritime shipments, this is commonly the ocean freight.
Insurance
Cargo insurance, where applicable.
Import Costs
Potentially:
- Customs duties
- Import taxes
- Customs clearance
- Inspection
- Government fees
Destination Costs
Potentially:
- Destination terminal charges
- Port handling
- Storage
- Local transportation
- Delivery to warehouse
- Unloading
Not every shipment contains every component.
The correct calculation depends on the transaction.
Step 1: Start With the Correct Purchase Price
The first step is identifying the actual commercial price of the stone.
For example:
Natural stone blocks: $30,000
But before using that figure, determine what the quotation actually means.
Is it:
- EXW?
- FCA?
- FOB?
- CFR?
- CIF?
- DAP?
- Another delivery term?
The Incoterm determines which costs have already been included in the seller’s quotation and which costs must be added by the buyer.
A $30,000 EXW quotation and a $30,000 CIF quotation do not represent the same commercial offer.
The quoted amount may be identical, while the buyer’s total landed cost can be dramatically different.
Step 2: Identify What the Incoterm Already Includes
This is one of the most important steps.
Before adding costs to the calculation, create a clear cost responsibility map.
For example:
| Cost Component | EXW | FOB | CFR | CIF |
|---|---|---|---|---|
| Stone purchase price | Seller quotation | Seller quotation | Seller quotation | Seller quotation |
| Factory pickup | Buyer | Depends on agreed obligations | Seller obligations as applicable | Seller obligations as applicable |
| Export clearance | Buyer under EXW rule | Seller | Seller | Seller |
| Main freight | Buyer | Buyer | Seller | Seller |
| Insurance | Buyer | Buyer | Buyer | Seller’s CIF obligation |
| Import clearance | Buyer | Buyer | Buyer | Buyer |
| Import duties/taxes | Buyer | Buyer | Buyer | Buyer |
| Destination delivery | Buyer | Buyer | Buyer | Buyer |
This is a simplified commercial overview rather than a substitute for the full Incoterms® 2020 rules.
The exact allocation must be checked against the selected rule and the named place or port.
For example, under CFR and CIF the seller pays the main freight, but the risk does not remain with the seller until the destination. Under those rules, risk transfers when the goods are delivered on board the vessel at the port of shipment.
Step 3: Calculate Origin Costs
If the quoted price does not include all origin-side costs, these must be added.
Potential origin costs include:
Inland Transportation
Moving the stone from the quarry or factory to:
- Port
- Rail terminal
- Container terminal
- Border crossing
- Consolidation facility
For natural stone blocks, inland transportation can be significant because of the cargo’s weight and dimensions.
Loading
Depending on the transaction, loading may involve:
- Forklifts
- Cranes
- Specialized lifting equipment
- Labor
- Securing materials
Export Clearance
Export customs procedures and related documentation may generate costs depending on the country and shipment structure.
Origin Terminal Charges
These may include:
- Terminal handling
- Documentation
- Port service charges
- Container-related charges
The important principle is:
Do not add a cost twice.
If the seller’s quotation already includes a particular origin charge under the selected Incoterm, do not add it again to the landed-cost calculation.
Step 4: Add International Freight
International transportation is often one of the largest components of landed cost for natural stone.
For maritime shipments, freight may depend on:
- Origin port
- Destination port
- Shipping line
- Container type
- Cargo weight
- Volume
- Route
- Season
- Market conditions
- Surcharges
- Booking conditions
For example:
Ocean Freight = $3,500
That amount should be added only if it is not already included in the supplier’s quoted price.
If the supplier offers the stone on a CFR or CIF basis, the main freight is generally already incorporated into the quoted commercial price.
The importer should therefore avoid adding it again.
Step 5: Add Cargo Insurance
Insurance depends heavily on the selected Incoterm and the buyer’s insurance arrangements.
Under CIF, the seller has an insurance obligation under the Incoterms® rule, but the buyer should not automatically assume that the provided coverage is comprehensive.
For a high-value natural stone shipment, the importer should review:
- Insured value
- Coverage
- Exclusions
- Deductible
- Claims procedure
- Covered transportation stages
- Handling coverage
- Damage coverage
Under Incoterms® 2020, CIF contains a specific insurance obligation, but the buyer should understand the scope of that obligation rather than treating “CIF” as synonymous with comprehensive cargo insurance.
For shipments under EXW, FOB, or CFR, the buyer may need to arrange insurance separately.
Step 6: Determine the Customs Value
This is where landed-cost calculation becomes more technical.
The customs authority may determine the customs value according to the country’s applicable customs valuation framework.
Under the WTO Customs Valuation Agreement, the primary method is the transaction value method, subject to its conditions and required adjustments. If that method cannot be used, the agreement provides additional valuation methods in a defined hierarchy.
The World Customs Organization identifies six valuation methods under the WTO framework:
- Transaction value
- Transaction value of identical goods
- Transaction value of similar goods
- Deductive value
- Computed value
- Fallback method
The methods are applied in the prescribed order when the earlier method cannot be used.
This matters because the importer should never assume:
Invoice Price = Customs Value
The two may coincide in some circumstances, but customs valuation rules can require specific additions or adjustments.
Step 7: Calculate Import Duty
Once the applicable customs value and tariff classification have been determined, the importer can calculate the applicable customs duty.
For an ad valorem duty:
Import Duty = Customs Value × Duty Rate
For example, purely for illustration:
Customs Value = $30,000
Duty Rate = 5%
Therefore:
Import Duty = $30,000 × 0.05 = $1,500
This is only an illustrative calculation.
The actual duty rate depends on the importing country’s tariff classification, origin rules, applicable trade agreements, and other national requirements.
WTO explains that ad valorem duties are calculated as a percentage of customs value, while specific duties are based on another quantitative measure rather than value.
Therefore, an importer must establish the correct tariff classification before relying on a landed-cost estimate.
Step 8: Account for Import Taxes
Import taxes may include:
- VAT
- GST
- Sales tax
- Other import-related taxes or levies
The calculation base differs between jurisdictions.
In some countries, an import tax may be calculated using a base that incorporates customs value, duties, and certain other costs.
Therefore, there is no universal formula such as:
VAT = Purchase Price × VAT Rate
That can be incorrect.
The importer must determine the tax base specified by the destination country’s legislation.
Step 9: Add Customs Clearance Costs
Customs clearance may involve:
- Customs broker fees
- Declaration fees
- Documentation
- Inspection
- Examination
- Government processing charges
- Port-related customs services
These costs are commercial expenses of the import transaction and should be included in the landed-cost model where applicable.
Step 10: Add Destination Port and Terminal Charges
A shipment arriving at the destination port can generate additional costs before the cargo reaches the buyer’s warehouse.
Depending on the shipment, these may include:
- Terminal handling charges
- Port fees
- Documentation fees
- Handling
- Storage
- Demurrage
- Detention
- Examination
- Container release fees
These charges are particularly important because they may not be obvious when comparing supplier quotations.
A shipment with a competitive CIF price can still generate substantial destination-side expenses.
Step 11: Add Final Inland Transportation
The final transportation leg is often forgotten.
For example:
Destination Port → Buyer’s Warehouse
might involve:
- Trucking
- Rail
- Local handling
- Unloading
- Special equipment
For natural stone blocks, the cost can be higher than ordinary cargo because of:
- Weight
- Dimensions
- Loading requirements
- Vehicle limitations
- Special handling
For slabs, packaging and palletization can also influence the transportation economics.
Step 12: Calculate the True Landed Cost
After all applicable components have been identified:
Landed Cost =
Purchase Price
+ Origin Transportation
+ Export/Origin Charges
+ International Freight
+ Insurance
+ Import Duty
+ Import Taxes
+ Customs Clearance
+ Destination Charges
+ Final Inland Transportation
+ Other Applicable Costs
This is the figure the importer should use for commercial comparison.
A Worked Example: Importing Natural Stone Blocks
Consider a hypothetical shipment of natural stone blocks.
Assume:
Stone purchase price: $25,000
Inland transportation: $1,200
Export/origin charges: $400
Ocean freight: $3,000
Cargo insurance: $150
Customs duty: $1,500
Customs clearance: $250
Destination charges: $600
Final inland transportation: $750
Assume, purely for illustration, that the applicable import tax is $2,100.
The estimated landed cost would be:
| Cost | Amount |
|---|---|
| Stone purchase | $25,000 |
| Inland transportation | $1,200 |
| Origin charges | $400 |
| Ocean freight | $3,000 |
| Insurance | $150 |
| Import duty | $1,500 |
| Customs clearance | $250 |
| Destination charges | $600 |
| Final inland transportation | $750 |
| Import tax | $2,100 |
| Total Landed Cost | $34,950 |
The stone was purchased for:
$25,000
But its estimated landed cost is:
$34,950
That means the buyer’s actual acquisition cost is approximately:
$9,950 above the original stone purchase price.
This is why evaluating the supplier purely by the initial quotation can produce misleading procurement decisions.
Calculate Landed Cost Per Ton
For natural stone blocks, buyers may also need to calculate landed cost by weight.
Suppose:
Total landed cost = $34,950
Shipment weight = 22 tons
Then:
Landed Cost per Ton = $34,950 ÷ 22
= $1,588.64 per ton
This can be useful when comparing:
- Different quarries
- Different suppliers
- Different origins
- Different logistics routes
However, buyers should ensure that the comparison is made using equivalent stone specifications and shipment conditions.
Calculate Landed Cost Per Square Meter
For slabs or tiles, a more useful commercial metric may be the landed cost per square meter.
Suppose:
Total landed cost = $34,950
and the shipment produces:
1,000 m² of saleable stone
Then:
Landed Cost per m² = $34,950 ÷ 1,000
= $34.95/m²
But there is an important issue.
For natural stone blocks, buyers should not simply divide the block purchase price by the theoretical surface area.
The correct analysis may need to account for:
- Block dimensions
- Saw kerf
- Slab thickness
- Cutting loss
- Cracks
- Natural cavities
- Edge trimming
- Resin treatment
- Non-saleable material
- Breakage
- Final usable yield
This is why landed cost per saleable square meter can be considerably more meaningful than landed cost per block.
Landed Cost Per Saleable Square Meter
Consider a block that generates:
1,200 m² theoretical production
but after processing and quality losses only:
1,000 m² saleable material
If the landed cost is:
$34,950
then:
$34,950 ÷ 1,000 = $34.95/m²
If the importer incorrectly assumes 1,200 m² of usable production:
$34,950 ÷ 1,200 = $29.13/m²
That creates a difference of:
$5.82/m²
This demonstrates why yield is an essential part of professional natural stone procurement.
The cheapest block is not necessarily the cheapest block per saleable square meter.
The Relationship Between Landed Cost and Block Yield
For rough blocks, landed cost should ideally be evaluated alongside expected production yield.
A useful conceptual model is:
Effective Cost per Saleable m² = Total Landed Block Cost ÷ Saleable Output
This allows buyers to compare two blocks with different purchase prices.
Example
Block A
Purchase + logistics + import:
$30,000
Expected saleable output:
1,000 m²
Effective cost:
$30/m²
Block B
Purchase + logistics + import:
$33,000
Expected saleable output:
1,300 m²
Effective cost:
$25.38/m²
Block B costs $3,000 more to acquire.
But it produces a lower effective cost per saleable square meter.
This is one of the most important reasons professional natural stone procurement cannot be based solely on the block price.
How Incoterms Change Landed Cost
Incoterms are particularly important when comparing landed cost.
Suppose a supplier offers:
Supplier A
EXW — $20,000
Supplier B
FOB — $23,000
Supplier C
CFR — $26,000
Supplier D
CIF — $26,500
These prices cannot be compared directly.
Why?
Because the included costs differ.
With EXW, the buyer may need to add substantial origin and transportation costs.
With FOB, the buyer generally arranges the main carriage.
With CFR, the seller arranges and pays the main freight.
With CIF, the seller arranges and pays the main freight and obtains the insurance required under CIF.
The correct method is to normalize all offers to the same landed destination.
The “Normalize the Quote” Method
When comparing international natural stone suppliers, use this process:
Step 1
Write down the supplier’s quoted price.
Step 2
Record the Incoterm and exact named place or port.
Step 3
Identify everything included in the quotation.
Step 4
List every cost that remains the buyer’s responsibility.
Step 5
Estimate import duties and taxes.
Step 6
Add destination charges.
Step 7
Add final transportation.
Step 8
Calculate total landed cost.
Step 9
Calculate cost per ton, block, slab, or saleable m² as appropriate.
Step 10
Compare suppliers only after all offers have been normalized.
This creates a much more meaningful procurement comparison.
Common Landed-Cost Mistakes When Importing Natural Stone
1. Comparing EXW With CIF Prices
This is one of the most common mistakes.
A lower EXW price does not automatically mean a lower total cost.
2. Forgetting Destination Charges
Importers often focus on:
Stone + Ocean Freight
and forget:
- Terminal charges
- Customs broker
- Storage
- Local delivery
- Unloading
These can materially change the final cost.
3. Double-Counting Freight
If freight is already included in a CFR or CIF quotation, do not add the same freight again.
Always identify the commercial scope of the quotation first.
4. Treating Customs Value as Landed Cost
Customs value is used for customs purposes.
Landed cost is a commercial acquisition-cost calculation.
They serve different purposes.
5. Assuming Invoice Value Is Always Customs Value
The WTO customs valuation framework uses transaction value as the primary method when its conditions are met, but specified adjustments can apply. The WCO explicitly notes that customs value does not necessarily equal the invoice amount.
6. Ignoring Import Taxes
An importer who calculates only:
Product + Freight + Duty
may still be missing significant tax obligations.
The exact tax base and recoverability of taxes depend on the destination country and the importer’s tax status.
7. Ignoring Yield
For natural stone blocks, this can be one of the most expensive mistakes.
The relevant metric is often not:
Cost per Block
but:
Cost per Saleable m²
8. Ignoring Damage and Quality Loss
Natural stone is a natural material.
Some material may become:
- Non-saleable
- Lower grade
- Smaller format
- Remnant material
The effective commercial cost should therefore be considered against realistic saleable output.
9. Ignoring Currency Risk
If the stone is purchased in USD but inland transportation, taxes, or destination charges are paid in another currency, exchange-rate movements can affect the final landed cost.
For long procurement cycles, this can be material.
10. Ignoring Demurrage and Storage
Unexpected delays at the destination can generate additional charges.
A professional importer should therefore distinguish between:
Expected Landed Cost
and
Worst-Case Landed Cost Exposure
Landed Cost Should Have Three Levels
For sophisticated procurement, it can be useful to calculate three scenarios.
Base Case
Normal transportation and customs clearance.
Conservative Case
Higher freight, additional handling, moderate delay, or higher destination costs.
Worst Case
Significant delay, storage/demurrage, inspection, additional handling, or other exceptional charges.
For example:
| Scenario | Estimated Landed Cost |
|---|---|
| Base | $34,950 |
| Conservative | $36,500 |
| Worst Case | $39,000 |
This provides management with a better understanding of procurement risk than relying on a single number.
Landed Cost vs. Total Cost of Ownership
Landed cost should also be distinguished from Total Cost of Ownership (TCO).
Landed cost generally focuses on getting the imported goods to the defined destination.
TCO can go further and include:
- Processing
- Fabrication
- Storage
- Financing
- Inventory carrying cost
- Waste
- Installation
- Maintenance
- Returns
- Quality claims
- Warranty exposure
For a natural stone importer, landed cost is therefore an important component of TCO—but not necessarily the entire economic picture.
A Professional Natural Stone Landed-Cost Worksheet
Before placing an international order, the buyer should build a cost sheet containing at least:
Product
- Stone type
- Quarry
- Block/slab/tile
- Grade
- Quantity
- Purchase price
Commercial Terms
- Currency
- Incoterm
- Named place/port
- Payment terms
Origin
- Factory loading
- Inland transportation
- Export clearance
- Origin handling
- Documentation
International Transport
- Freight
- Insurance
- Surcharges
Import
- Customs value
- HS/tariff classification
- Duty
- Import tax
- Customs broker
- Inspection
Destination
- Port charges
- Terminal handling
- Storage
- Demurrage/detention
- Local transportation
- Unloading
Production Economics
For blocks:
- Expected yield
- Saleable output
- Processing loss
- Effective cost per saleable m²
For slabs:
- Number of slabs
- Saleable area
- Breakage
- Quality downgrade
This gives the buyer a much more realistic commercial picture.
A Simple Landed Cost Formula for Natural Stone Buyers
For practical procurement, the following model is useful:
Total Landed Cost
= Stone Purchase Price
- Origin Logistics
- Export Costs
- International Freight
- Insurance
- Import Duty
- Import Taxes
- Customs Clearance
- Destination Charges
- Final Delivery
- Other Applicable Costs
Then:
Landed Cost per Unit
= Total Landed Cost ÷ Saleable Quantity
For blocks:
Landed Cost per Saleable m²
= Total Landed Block Cost ÷ Expected Saleable m²
For slabs:
Landed Cost per Saleable m²
= Total Landed Slab Cost ÷ Saleable Slab Area
The final formula should always reflect the actual commercial structure of the transaction.
A Better Way to Compare Natural Stone Suppliers
Instead of asking:
“Which supplier has the lowest price?”
A professional importer should ask:
“Which supplier provides the lowest comparable landed cost for the required quality and saleable output?”
That difference is substantial.
A supplier offering:
$18/m²
may not be cheaper than one offering:
$21/m²
if the first supplier has:
- Higher freight
- Higher import costs
- Lower yield
- More breakage
- More quality variation
- Higher processing losses
The correct comparison is the economic cost of usable material, not merely the supplier’s advertised price.
The Five Numbers Every Natural Stone Buyer Should Know
Before approving an international purchase, the buyer should ideally know:
1. Purchase Cost
How much is being paid to the supplier?
2. Logistics Cost
How much will it cost to move the stone internationally?
3. Import Cost
What will customs, duties, taxes, and clearance add?
4. Landed Cost
What is the total acquisition cost at the defined destination?
5. Effective Cost of Saleable Material
After yield, breakage, and quality losses, what does the usable stone actually cost?
The fifth number is often the most commercially meaningful for processors and distributors.
Final Example: Why the Cheapest Supplier May Not Be the Cheapest
Consider two hypothetical block suppliers.
Supplier A
Block price:
$24,000
Estimated landed cost:
$32,000
Saleable production:
1,000 m²
Effective cost:
$32/m²
Supplier B
Block price:
$27,000
Estimated landed cost:
$34,000
Saleable production:
1,400 m²
Effective cost:
$24.29/m²
Supplier B has the higher purchase price.
Supplier B also has the higher landed cost.
But Supplier B produces substantially more saleable material.
Therefore:
Supplier B provides the lower effective cost per saleable m².
This is the kind of analysis that separates professional natural stone procurement from simple price comparison.
Final Takeaway
The true cost of imported natural stone does not end with the supplier’s quotation.
A professional importer should evaluate the complete commercial chain:
Purchase → Origin Logistics → Export → Freight → Insurance → Customs → Duties & Taxes → Destination → Delivery → Saleable Output
The result is the buyer’s real economic exposure.
The most important principle is therefore:
Do not compare natural stone suppliers by purchase price alone. Compare them by normalized landed cost and, where relevant, by landed cost per unit of saleable material.
For international natural stone buyers, this approach provides a much more reliable basis for supplier selection, quotation analysis, project costing, and procurement decisions.
At the same time, buyers should keep landed cost, customs value, and total cost of ownership as separate concepts. Customs valuation follows the applicable customs framework, while landed cost is a commercial calculation of the total acquisition expense. The WCO and WTO frameworks emphasize transaction value as the primary customs valuation method when its conditions are satisfied, with specific adjustments and alternative methods where required.
A well-structured landed-cost model therefore does more than tell an importer what a shipment costs.
It reveals where the money is actually going—and whether the purchase is commercially competitive.
Frequently Asked Questions
Is landed cost the same as the purchase price?
No. Purchase price is only one component of landed cost. Landed cost can include transportation, insurance, customs duties, taxes, clearance, destination charges, and other applicable costs.
Is landed cost the same as customs value?
No. Customs value is a customs valuation concept used, among other things, to calculate ad valorem duties. Landed cost is a broader commercial calculation of the total acquisition cost.
Does CIF automatically represent the final landed cost?
No. CIF generally includes the seller’s cost, freight, and required insurance under the CIF rule, but import duties, taxes, customs clearance, destination charges, and final delivery may still be payable by the buyer.
Should freight be added to a CFR quotation?
The main freight is generally already included in the CFR price. It should not be added a second time. However, other destination-side costs may still need to be included.
How do I calculate landed cost for natural stone blocks?
Calculate the total acquisition cost of the shipment and then, where useful, divide it by the expected saleable output. For commercial stone processing, landed cost per saleable square meter can be more informative than landed cost per block.
Why is yield important?
Because two blocks with different purchase prices can produce very different quantities of saleable material. A higher-priced block can ultimately have a lower effective cost per saleable square meter.
Can landed cost be calculated before importing?
Yes. In fact, it should ideally be estimated before the purchase is finalized. The calculation can then be updated using actual freight, customs, handling, and destination costs after shipment.
Can customs duties be calculated simply as a percentage of the invoice price?
Not always. The applicable customs valuation rules determine the customs value, and the WTO/WCO framework provides for specific adjustments and valuation methods. The invoice amount and customs value are not necessarily identical.
Authoritative References
For a professional article on landed cost and customs valuation, the strongest external references are primary or intergovernmental sources:
- World Customs Organization (WCO) — Customs Valuation: explains customs value, transaction value, adjustments, and the international customs valuation framework.
- World Trade Organization (WTO) — Customs Valuation Agreement: provides the international legal framework for customs valuation and the hierarchy of valuation methods.
- WTO — Technical Information on Customs Valuation: explains transaction value, ad valorem duties, and the distinction between customs valuation and other costs.
- WCO Trade Tools — Valuation: provides technical information on customs valuation and the role of transaction value.
Editorial note: Landed-cost calculations are country- and transaction-specific. Import duties, taxes, customs valuation adjustments, tariff classification, and destination charges should be verified with the customs authority, qualified customs broker, or trade professional in the importing country before a commercial transaction is finalized.